The present disclosure relates generally to plant genetics and plant molecular biology, and more particularly relates to compositions, systems and methods of conferring disease resistance to plant pathogens that express pathogen-specific proteases based on recognition of the pathogen-specific proteases in a plant cell.
Plant diseases are a serious limitation on agricultural productivity and influence the development and history of agricultural practices. A variety of plant pathogens are responsible for plant diseases including bacteria, fungi, insects, nematodes and viruses.
Incidence of plant diseases can be controlled by agronomic practices that include conventional breeding techniques, crop rotation and use of synthetic agrochemicals. Conventional breeding methods, however, are time-consuming and require continuous effort to maintain disease resistance as plant pathogens evolve. See, Grover & Gowthaman (2003) Curr. Sci. 84:330-340. Likewise, agrochemicals increase costs to farmers and cause harmful effects on the ecosystem. Because of such concerns, regulators have banned or limited the use of some of the most harmful agrochemicals.
Agricultural scientists now can enhance plant pathogen resistance by genetically engineering plants to express anti-pathogen polypeptides. For example, potatoes and tobacco plants have been developed that exhibit an increased resistance to foliar and soil-borne fungal pathogens. See, Lorito et al. (1998) Proc. Natl. Acad. Sci. USA 95:7860-7865. In addition, transgenic barley has been developed that exhibit an increased resistance to fungal pathogens. See, Horvath et al. (2003) Proc. Natl. Acad. Sci. USA 100:364-369. Moreover, transgenic corn and cotton plants have been developed to produce Cry endotoxins. See, e.g., Aronson (2002) Cell Mol. Life Sci. 59:417-425; and Schnepf et al. (1998) Microbiol. Mol. Biol. Rev. 62:775-806. Other crops, including potatoes, have been genetically engineered to contain similar endotoxins. See, Hussein et al. (2006) J. Chem. Ecol. 32:1-8; Kalushkov & Nedved (2005) J. Appl. Entomol. 129:401-406 and Dangl et al. (2013) Science 341: 746-751.
In light of the significant impact of plant pathogens on the yield and quality of plants, additional compositions, systems and methods are needed for protecting plants from plant pathogens.